What changes at 2000-2500 rpm?

[GreenChevelleSS]

Still trying to figure this crap out with my 2000-2500 rpm misfire. It happens no matter the throttle position. never missing below 2000 rpm and above 2500. It seems to do it more when the engine is cold, but still does it hot.
Swapped the coil packs, ignitor, cps. Installed new plugs, wires, TPS, timing belt.

 

[GC89]

Fuel pump resistor circuit or afm load point would be my guess

 

[GreenChevelleSS]

I bypassed the load resistor already. I had the same thought. I messed with the tune in that area and got no change.

 

[7MGTEsup]

Are you on AEM V1?

 

[Nick M]

Turn your Fluke to Hz and see if you have repeating results at certain frequency. In one of the older manuals, it lists Hz for a short rpm range, maybe even to 2500. I will look and see. It lists it at no load only off the top of my head.


edit: not idle, at no load and 3000 rpm

 

[hvyman]

Like misfiring or 1 big cutout misfire?

 

[Nick M]

Ks signal is 30 Hz @ 700 rpm, 90 Hz @ 2500 rpm, 170 Hz @ 4000 rpm. It is worth checking against known good units. The numbers will be about 25% lower with the 1UZFE meter. As we all know.